New solar research projects at the Ira A. Fulton Schools of Engineering will receive $3.75 million in funding the U.S. Department of Energy SunShot Initiative announced today. The home of the Engineering Research Center for Quantum Energy and Sustainable Solar Technologies, Arizona State University garnered five of 19 awards, more than any other institution receiving funding. The awards amount to nearly 20 percent of the funds allocated, each with the potential to dramatically reduce solar energy costs.
The SunShot Initiative’s photovoltaics program, which is the focus of the current round of funding, supports research and development projects that lower manufacturing costs, increase efficiency and performance, and improve reliability of PV technologies in order to support widespread deployment of electricity produced directly from sunlight. The PV portfolio includes research directed toward the SunShot Initiative goals as well as critical challenges beyond 2020.
Stacking yields broader solar harvest, reduces costs

Postdoctoral researcher Mathieu Boccard, front, and electrical engineering Assistant Professor Zach Holman work on solar cells in Holman’s lab. Photographer: Jessica Hochreiter/ASU
In May, a unique collaboration between researchers led by electrical engineering Professor Yong-Hang Zhang and Assistant Professor Zachary Holman wedded two previously disparate solar cell technologies, taking another step toward lower-cost and widely accessible solar power.
The results of their partnership not only broke an efficiency record by a large margin for monocrystalline cadmium telluride cells, but more importantly, also achieved the highest open-circuit voltage ever recorded for a cell of its type.
Now with a new $400,000 award, the partnership between the two research groups will continue, investigating the fabrication of high-efficiency, “stacked” photovoltaic cells, which comprise of two different types of cells. The pair is also collaborating with Wyatt Metzger, of the National Renewable Energy Laboratory in Golden, Colorado.
“The long-term aim of this project is to stack two different solar cells on top of one another, one of which is efficient at converting visible light into electricity and one of which is efficient at converting infrared light into electricity,” explains Holman. “We call this a tandem solar cell.”